Gen Prayut said that each referendum on constitutional amendments would require about B4 to 5bn, with costs that include spending on COVID-19 prevention measures.
Gen Prayut said the cabinet approved, in principle, the bill which was proposed by the Election Commission (EC).
The EC explained to the cabinet that at least two referendums are required - one on the amendment of the charter change process to set up a charter drafting body, and another on the new charter, Gen Prayut said.
According to political analysts, in the first referendum, voters would decide whether they agree with the proposal to establish a charter drafting assembly to write a new charter.
If they do, the process would go ahead. When the new body finishes the new charter, the new charter would then be put to a referendum again.
Citing an estimate by the EC, Gen Prayut said that normally a referendum costs about B3bn to hold, but with the COVID-19 pandemic, another B1bn would be needed to arrange more polling stations than usual so as to ensure each station is not overcrowded.
No more than 600 voters are allowed at each station. This would require more funding, the prime minister said.
“I’m just letting you know [about the cost]. Don’t accuse me of not supporting [charter amendments]. If I didn’t support it, I would not push for the referendum bill,” Gen Prayut said.
Rachada Dhnadirek, a deputy government spokeswoman, said that Section 166 of the constitution allows the cabinet to hold a referendum on issues that do not violate the constitution.
Under the referendum bill, a vote will be direct and secret, she said, adding that the bill is in line with Section 256 of the constitution.
The section stipulates that a national referendum is required if a would-be amendment involves the charter amendment process, the chapters on general principles and the monarchy.
The next step will be to forward the bill to the Council of State - the government’s legal advisory body - to scrutinise.
The bill will then go to government whips who will submit it to parliament, Ms Rachada said.
On Sept 1, parties in the coalition government tabled a motion seeking to amend the constitution to parliament, including details of the formation of a panel which will write a new charter.
The thrust of the motion will be to amend Section 256 of the constitution, which would allow the charter drafting assembly to be formed to draw up a new charter.
Section 256 also says charter changes require the support of at least one-third of the Senate, or 84 senators.
These requirements are widely seen as a being major hurdle to rewriting the constitution, which was enacted by the previous coup-installed government.
The charter amendment process was set in motion after students launched a series of anti-government protests in July. One of their demands was to rewrite the constitution.
In related news, Pheu Thai Party MPs and executives met yesterday to discuss charter amendments.
Pheu Thai leader Sompong Amornvivat said the party’s version of a charter rewrite bill also calls for a new charter writing body to be set up.
The bill, tabled before parliament on Aug 17, seeks to strip away the power of the current Senate, which was set up and installed by the now-defunct National Council for Peace and Order, Mr Sompong said.
He added parliament will consider versions of charter amendment bills from the opposition and coalition parties in their first reading on Sept 23 to 24. However, the current parliament session will end on Sept 25. The next session will begin on Nov 1.
Mr Sompong said that efforts will be made to gather the support of at least 250 lawmakers from opposition and coalition parties.